Apparatus for transmitting sounds by means of hertzian waves.



W. HARRISON.

APPARATUS FOR TRANSMITTING SOUNDS BY MEANS OF HERTZIAN WAVES.

APPLICATION FILED OCT. 2|

2 SHEETS-SHEET I.

Patented May 11, 1915.

l mgmaeo %itmeooeoz awvevwoz w. HARRISON.

APPARATUS FOR TRANSMITTING SOUNDS BY MEANS OF HERTZIAN WAVES.

LNEQATSO A Wane wee:

APPLICATION FILED-OCT.2I, I914- Patented May 11, 1915.

2 SHEETS-SHEET 2- WALTON HARRISON, OF NEW YORK, N. Y.

APPARATUS FOR TRANSMITTING SOUNDS BY MEANS OF HERTZIAN WAVES.

1,139,4113. Original application filed March 11, 1902, Serial No.

Specification of Letters Patent.

Patented May 11,1015.

97,728. Divided and this application filed October 21,

1914., Serial No. 867,855.

T all whom it may concern Be it known that :1, WALTON HARRISON, a citizen of the United States, residing in the city of New York, borough of Manhattan, in the county and State of New York, have invented new and useful Apparatus for Transmitting Sounds by Means of Hertzian Waves, of which the following is a specification.

My invention relates to the transmission of sounds to a distance by aid of Hertzian waves, commonly designated as electromagnetic waves.

Generally speaking, I seek to impress the Hertzian waves with arbitrary characteristics or undulations analogous to sound waves, and to cause the Hertzian waves, thus impressed, to traverse a distance and control the production of sounds.

Many difierent forms of mechanical apparatus may be used in the practice of my invention, and it is impracticable to describeall of them without undue prolixity. However, 1 will describe a few simple forms, together with typical electric circuits and simple mechanical devices associated therewith and included within the invention.

This application is a division of my application Serial No. 97,728, filed March 11, 1902, resulting in Patent No. 1,118,004, dated November 24, 1914:, for art of transmitting sounds by means of Hertzian waves.

Reference is to be made to the accompanying drawings forming a part of this specification, and in which like letters indicate like parts.

Figure 1 is a diagrammatic plan of one form of my transmitter. Fig. 2 is a diagrammatic plan of one form of my receiver. Fig. 3 is a side elevation, partly in section, of said receiver and transmitter, separated by a wall. Fig. 4 is an elevation of the mouth-piece of the transmitter. Fig. 5 is a diagrammatic plan, partly in section, showing another form of my transmitter.

Mounted upon a bracket 1 is a mouthpiece 2, provided with a vibratory diaphragm 3, all of which parts may be made of any preferred materials. Carried by the diaphragm is a depending apron 4, having a slot 5. The parts are so arranged and adjusted that the production of sounds adjacent to the mouthpiece will cause the diaphragm and apron to vibrate, thereby causing the slot 5 to move bodily back and forth,

in a direction at right angles to the general plane of the diaphragm.

For the purpose of producing a static discharge a. pair of polished knobs 6, 7 mounted upon posts 8, 9 are connected by wires 10, 11,'with the secondary winding 12 of a large Ruhmkorfl coil A, which is provided with the usual primary winding 13, core 14; and circuit breaker 15, together with a switch 16 for cutting out the circuit breaker at will. The primary winding 13 is further connected, by wires 17, 18, with the primary winding 19 of a comparatively small Ruhmkorfi' coil B. The secondary winding 21 of this coil is connected, by wires 23, 2 1 and switches 29, 30, with a pair of pointed elec-' trodes 25, 26, mounted upon posts 27, 28. The primary windings of the two coils are thus placed in a common circuit, which is excited either by a battery 29*, and circuit breaker 15, or by an alternating dynamo 30, as desired. When the battery 29 is used the switches 16 and 31 are open and the switch 32 is closed. When the dynamo 30* is used, the switch 32 is open and the switches'16 and 31 are closed. The exciting currents, whether direct or alternating, thus pass through two primary windings, simul taneously, the direction of the flow at any particular instant being alike for the two coils. The primary currents should be of high frequency.

By means of switches 34, 35, 36, 37, inductance windings 38, 39 and wires 41, 42, the pointed electrodes 25, 26 may be shunted from the secondary circuit of the large coil A. For this purpose the switches 29, 30 are opened and the switches 34:, 35, 36 and 37 are left closed. This enables the pointed electrodes to be energized by the large coil A. When, however, it is desirable that the pointed electrodes be energized by the small coil B, the switches 29 and 30 are left closed and the switches 3T, 35, 36 and 37 are opened.

The inductance windings 38, 39, are never used except in instances where the pointed electrodes 25, 26 are connected in shunt, as above described, with the secondary winding 12 of the large coil A. The purpose of the windings 38, 39 is to prevent the shunt circuit from diverting too much electricity from the knobs, where it is most needed, to the pointed electrodes, where a comparatively weak discharge will suffice. So, also,

the coil A is larger than the coil 13 because the discharge between the knobs 6, 7 is preferably far more powerful than that between the pointed electrodes. The ointed electrodes, like the knobs, are ad]ustab1e relatively to each other.

N o matter whether the pointed electrodes are energized, as above described, by the coil B or by the shunt from the knobs 6, 7, one effect is the same, to wit, two distinct and arallel discharges occur continuously; one

eing a powerful discharge crossing the gap between the knobs and characterized by a bright spark; and the other being a weaker discharge evidenced by a comparatively short spark located between the pointed electrodes. The powerful spark discharge between the knobs is the one used in generating the Hertzian waves, which are normally propagated in the usual 'manner. The smaller spark is for the sole purpose of radiating ultra violetlight upon the knobs, through the slot 5.

The apron 4 is made of mica, paper or any other substance opaque to the utlra violet rays, so as to screen the knobs from said rays except when the latter pass through the slot. The action of the utlra violet rays is entirely local. A screen 43, preferably of manifold wire gauze, is provided in order to obstruct the passage of any Hertzian waves incidentally generated by the circuit for producing the ultra violet rays, and which might otherwise interfere with the Hertzian. waves, produced by aid of the knobs.

The receiving apparatus shown in Figs. 2 and 3' comprises a rotary coherer 44, provided with trunnions 45, 46, supported in conical bearings in the screws 47, 48, mounted in posts 49, 50. The coherer is provided with wings 51, 52, and is driven by clockwork 53 actuated by a weight 54. An impedance coil 53, a battery 56, and a telephonic receiver 57 are connected with the coherer by means of wires 58.

The operation of the apparatus is as follows: By manipulating various switches as above described, the two sparks are started. A sound to be transmitted is made at a point near the mouthpiece, and the diaphragm and apron are thus caused to vibrate. Hertzian waves are constantly propagated from the circuit of which the knobs form a part. The effect of the ultra violet rays, passing through the slot and falling upon the knobs, is to impair the strength of the Hertzian waves. The vibrations of the diaphragm therefore have the eflect of alternately weakening and strengthening the waves,

whereby the latter are impressed with undulations somewhat analogous to those of sound waves. That is to say, the alternate strengthening and weakening of groups of the Hertzian waves is analogous to the alternate condensations and rarefactions peculiar to sound waves. Normally, the diaphragm being at rest, the ultra violet light falls upon the knobs, preferably upon the lower halves thereof. The Hertzian waves are therefore normally weak. Upon each descent of the diaphragm the ultra violet rays being partially, or in extreme cases wholly, thrown off the knobs, the Hertzian waves are strengthened more or less. Vice versa, by each ascent of the diaphragm the Hertzian waves are weakened, the degree of strength parted to them being governed by the movements of the diaphragm. It follows, therefore, that every motion of the diaphragm, no matter what may be its frequency or amplitude, impresses its characteristic effect upon the Hertzian waves. It is essential that the Hertzian wave trains follow each other with great rapidity, so that a single sound wave affects a considerable group of Hertzian waves, thus rendering the sounds more distinct at the receivmg statlon. The oscillatory character of the sparks between the knobs need not be considered here. As the lmobs are located 'at a greater distance than the diaphragm from the source of ultra violet light, a comparatively small movement of the diaphragm causes the beam or zone of light to sweep laterally upon and adjacent to the knobs. The Hertzian waves are thus impressed arbitrarily with characteristics analogous to sound waves, and of variable intensity and difiering in frequency, in a manner somewhat similar to that in which a battery current is impressed by undulations from a carbon transmitter. The principle appears to be that the air or dielectric in the spark gap is ionized to different degrees by the varying quantities of ultra violet light falling upon the knobs. The Hertzian waves, thus impressed, are propagated to a distance, and may traverse media such as buildings, trees, earth,'etc., represented by the wall 73 in Fig. 3. When the Hertzian waves strike the wings 51, 52 they vary the resistance of the local or battery circuit at the receiving station and cause the telephonic receiver to reproduce the sounds made originally at the transmitting station.

Fig. 5 shows another form of my transmitter, in which, however, the ultra violet rays are not used.

The secondary winding 59 of the Ruhmkorff coil C is connected with the polished knobs 60, 61. The coil in question is provided with two distinct primarywindings 62, 66. The winding 62 is connected by Wires 63 with the battery 64 and circuit breaker 65. The winding 66 is connected by wires 67 with the battery 68,'mouthpiece 69,

diaphragm 70 and the usual carbon connections 71 and 72. The idea is, the current in over a considerable space same frequency as sound waves.

the coil 62 is interrupted automatically by the circuit breaker 65, while the current in the winding 66 is continuous, but varied by sounds upon the transmitter. It follows that while the rapidity of the circuit breaker is very great, so that the wave trains follow one another in rapid succession, the strength, quality, etc., of the waves is modified by the currents controlled by the sound waves. As a result, certain arbitrary groups of the Hertzian' waves are thus impressed with arbitrary undulations or characteristics analogous to sound waves, and having the In other of the transmitter circuit is to control the strength and quality of the sparks produced, thus governing the strength and quality of the Hertzian waves according as the sparks may be useful or useless. The electromagnetic waves, thus impressed, readily pass through vacant space and materials of divers kinds, the latter being represented by the obstacle 73, and afiect the receiver.

In adjusting the knobs, I make the spark gap a little longer or a little shorter than the distance representing maximum usefulness, so as to allow for both increases and decreases in usefulness due to variations in the supply of ultra violet light reaching the knobs and the gap therebetween.

As illustrating the control which the ultra-violet rays are capable of exercising over the spark discharge, I may say that when the transmitter. shown in Figs. 1, 3 and 4, which I call my violet ray transmitter, is used, the two spark gaps can be so adjusted that the descent of the diaphragm completely stops a spark normally plying between the knobs, and that the ascent of the diaphragm restores said spark. T find that when the pointed electrodes are so adjusted that no visible discharge passes between them, they still emit powerful ultra violet rays; also that when the knobs alone are sparking, the descent of the diaphragm may simultaneously stop the spark discharge between the knobs and start another one between the pointed electrodes, whereas the ascent of the diaphragm has the contrary efiect namely, stopping the spark dis charge between the pointed electrodes and starting one between the knobs. These incidents are mentioned as merely indicating the complete subordination of the static dischargeto the movements of the diaphragm, rather than as defining the normal action of the apparatus. They are extreme instances showing the maximum eliect of the light rays upon the spark gap, and consequently upon the Hertzian waves. In all cases the Hertzian waves are remarkably sensitive to vibratory motions of the diaphragm, to which they respond uantitatively.

The expression ertzian waves is herewords, the work in used in a broad sense, including not only the electromagnetic waves discovered by Hertz, but the various modifications thereof heretofore used in wireless telegraphy, whether serial, subterranean or submarine. I do not limit myself to the employment of electromagnetic waves in all instances, however, as obviously some parts of my apparatus may be used in other relations.

Having thus described my invention, what I clalm as new and desire to secure by Letters Patent is as follows l. The combination of a signaling circuit including a gap across which electricity flows for the purpose of controlling the strength of the signals, and means for exposing said ap to the action of varying quantities of 'ght controllable by sounds for afi'ecting the flow of said electricity across said ap. 2. he combination of a signaling circuit lncluding a gap across which electricity flows for the purpose of controlling the y I strength of the signals, and means for exposing said gap to the action of sound controlled ultra violet light.

- 3. The combination of a signaling circuit including a gap across which electricity flows for the purpose of controlling the strength of the signals, and means for exposing said gap to the action of an ionizing medium controllable sounds for varying the flow of electricity.

4:. The combination of a signaling circuit including a gap across which electricity flows for controlling the generation of electromagnetic waves, and means for subjectlng said gap to the quantitative action of ultra violet light varied in accordance with sound waves.

5. The combination of a signaling circuit including a gap across which electricity flows for controlling the generation of electromagnetic waves, and means for throwing into said gap, from a position extraneous thereto, varying quantities of an ionizing medium capable of quantitatively afiecting the fiow of said electricity across said gap.

' 6. The combination of a signaling circuit including a gap across which electricity flows for controlling the generation of electromagnetic waves, and means for throwing into said gap, from a position extraneous thereto, an ionizing medium quantitatively varied in accordance with sound waves.

7. The combination of a signaling circuit including a gap across which electricity flows for controlling the generation of electromagnetic waves, and means for throwing into said gap, from a position extraneous thereto, a medium varied after the manner of sound waves and capable of quantitatively afiecting the flow of said electricity across said gap.

8. The combination of a signaling circuit quantitatively by comprising a circuit including a gap, means for energlzing saidcircuit so as to cause successive electrical impulses to leap across said gap, and sound-controlled mechanism,

independent of said means, for quantitativelylvar ing the resistance of said gap.

comprising a circuit including a gap, means for energizmg said circuit so as to cause successive electrical impulses to leap across said gap, .and sound-controlled mechanism,

.' independent 'of said means, for exposing said gap to the action of varying quantities of ultra violet light.

11. A device of the character described, 7 comprising a circuit including a gap, means for energizing said circuit so as to cause successive electrical impulses to leap across said gap, and means for exposing said gap to ultra violet light, varied in accordance with sound waves.

12. The combination of an unclosed circuit provided with a gap, means for de-. veloping impulses of high frequency in said circuit, said impulses tending to cause high frequencydischarges across said gap, and means controllable by sound waves and local to said gap for ionizing the same.

13, The combination of a circuit provided with a gap, means for developing impulses of high frequency in said circuit, said impulses tending to cause high frequency discharges across said gap, and means controllable by sound waves for quantitatively exposing saidvl'gap to the action of ultra violet light.

14. In combination, a circuit including a gap across which a flow of electricity may take place; a source of electric energy for -said circuit; a source of radiant energy extraneous to said gap and capable of ionizing said gap; and means coacting with said source of radiant energy and controllable by sound waves for varying quantitatively said flow of electricity across said gap.

15. The combination of a circuit includ: ing a gap adapted for the passage of electricity thereacross for purposes of signaling,

and means for subjecting said gap to the difierential action of a radiating medium supplied thereinto in quantities varied after the manner of sound waves and capable of quantitatively controlling the flow of electricity across .said gap 16. The combination of with a gap, means forfenergizing said cirevice fof the character described,.

a circuit provided cuit by a succession'of impulses .so as to constantly maintain a high frequency discharge across said gap, and means for intermittently exposing said gap to the action of ultra violet light.

17. The combination of'a circuit providedwith a gap, means for energizing said circuit by a succession of impulses so as to constantly maintain a discharge across said gap, and mechanism controllable by sound waves for intermittently exposing said gap to the action of a radlating medium capable of varying the resistance of said gap.

' 18. The combination of a circuit provided with a gap, means for ener cuit by a succession of impu ses in order to constantly maintain a high frequency discharge across said gap, and mechanism operable during said high frequency discharge for the purpose of subjecting said gap to the action of an ionizing medium directed intermittently thereinto.

19. The combination of a with a gap, means for energizing said circuit by a succession of impulses in order to constantly maintain a high frequency discharge across said gap, and-mechanism operable while said high frequency discharge is taking place for subjecting said gap to zing said cir-- by a succession of impulses in order to constantly maintain a pulsating discharge across said gap, and mechanism operable while said discharge is taking place and controllable by sound waves for directing into said gap varying quantities 0 fan ionizing medium capable of quantitatively changing the character of said discharge.

22. The combination of a circuit provided with a gap, means for energizing said circuit by a succession of impulses in order to constantly maintain a pulsating discharge across said gap, and mechanism operable while said discharge is taking place and controllable by sound waves for directing into said gap varying quantities of aoradiating medium capable of quantitatively changing the character of said discharge.

23. The combination of an oscillation circuit provided with a gap, means for causing a discharge to take placeacross said gap in order to develop .oscillations in said circuit, andmechanism operable independently of said oscillation circuit and controllable by sound Waves for the purpose of quantitatively modifying the character of said discharge and thus varying the power of said oscillations. v

24. The combination of a circuit provided with a gap, mechanism controllable by sound Waves for directing into said gap varying quantities of an ionizing medium in order to quantitatively vary the resistance of said gap, means for causing electricity to flow across said gap While the resistance thereof is at its maximum and also While said resistance is below its maximum.

25. The combination of a circuit provided with a gap, a source of radial energy extraneous thereto, mechanism controllable by sound Waves for directing into said gap,

from said source, varying quantities of said radial energy capable of affecting the resistance of said gap quantitatively, and means operating independently of changes in resistance cl said gap for causing electricity to i'low across the gap.

26. The combination of a circuit provided with a gap, mechanism controllable by sound Waves for directing into said gap, from a point extraneous thereto, varying quantities of light capable of affecting the resistance i said gap, and means operating independently of changes in resistance or" said gap for causing electricity to flow across the gap.

27. The combination of a circuit provided with a gap, mechanism controllable by sound Waves for directing into said gap, from a point extraneous thereto, varying quantities of ultra violet light for changing the resistance of said gap, and means operating independently of changes in resistance of said gap for causing electricity to flow across the gap,

28. The combination of a circuit provided with a gap, means operating independently of changes in resistance of said gap for causing electricity to flow across the gap, and mechanism operated independently of the COIldltlOIl of said gap for subjecting said -ing electricity to flow across the mechanism operated independently of the ently of changes in resistance of said gap for causing electricity to flow across the gap, and mechanism operated independently of the condition of said gap for subjecting said gap to the action of radiant energy from said source capable of changing resistance of said gap.

30. The combination of a circuit provided with a gap, means operating indep ndently of changes in resistance of said gap for causgap, and

condition of said gap for exposing said gap to the ionizingaction of ultra violet light 31. The combination of a circuit provided with a gap, means operating indep ndently of changes in resistance of said for causing electricity to flow across the gap, and mechanism operated independently of the condition of said gap for directing into said gap, from a point extraneous thereto, varying quantities of light capable of titatively changing the resistance of and.

a 32. The combination of a circuit provided With a gap, means operating independently of changes in resistance of said gap for causing electricity to flow across the gap, and mechanism operated independently of the condition of said gap and controllable by sound Waves for subjecting said gap intermittently to the action of an ionizing me dium capable of changing the resistance of said gap.

In Witness whereof I have signed my name in the presence of two subscribing witnesses.

WALTON HARRISON. Witnesses L. ALTMAN, FRED. ROEGER. 

